Studio Technologies 5152 V.3 - Manual (Page 19)

Model 5152 User Guide Issue 2, June 2013
Studio Technologies, Inc. Page 19
Model 5152
Video Generator/Audio Embedder Module
No matter what the format and rate of the
connected SDI signals, the stored param-
eters will not change. Changing the stored
parameters would require the mode to be
changed to Auto Select, an SDI signal with
the desired format and rate be connected
for a minimum of five seconds, and then
the mode changed back to Locked.
Moving Image Overlay
The Model 5152 has the ability to overlay
a moving image on top of the stored “720”
and “1080” images. A configuration setting
selects whether the moving image overlay
will be active. The moving image, a box
that’s red in color, slowly moves around
and on top of whatever stored image is
present on the SDI output. The color, size,
and rate of motion of the “box” are fixed in
the FPGA’s firmware (embedded software)
and can’t be altered.
The moving image is provided specifically
so that users who are “downstream” from
the Model 5152’s SDI output are assured
that the “720” or “1080” image they are
viewing is active. And, just to clarify, if
a signal is present on the Model 5152’s
selected SDI input it will be passed on to
the coaxial (BNC) and, if present, optical
SDI outputs. The moving image will never
overlay an input signal—it can only overlay
on top of the stored image.
Audio Embedding
The Model 5152 can embed up to eight
audio channels into the SDI output signal.
These audio channels originate as four
digital audio pairs that are connected to
the digital audio inputs. Exactly how the
module embeds the audio depends on
how the module has been configured.
There are eight configuration choices
which are made using three switches that
are located on the rear of the Model 5152’s
FPGA board. Note that one of the eight
choices is to not embed at all, something
that’s included primarily as a test function.
Refer to Figure 7 to review a list of embed-
ding configuration choices.
There are eight signal present status LEDs
associated with the eight audio channels
that originate with the four digital audio
inputs. (Two audio channels are associ-
ated with each of the four AES3-compat-
ible digital audio inputs.) A signal present
LED will light when its associated audio
channel has met two conditions. The first is
that this channel (as part of a channel pair)
has been configured to be embedded. The
second is that signal level on that channel
must exceed –40 dBFS. This level is 20 dB
below the nominal audio level of –20 dBFS
for SMPTE applications. For EBU applica-
tions it will light 22 dB below the nominal
–18 dBFS level.
Audio will be embedded into the SDI
output signal whether or not an SDI input
(coaxial (BNC) or optical) signal is present.
If no signal is present on the SDI input the
custom image will be active and audio will
be embedded into it.
If a valid signal is present on the selected
SDI input it will pass through to the coaxial
(BNC) output and, if present, the optical
SDI output. The Model 5152 will embed
audio into the SDI input signal following
the selected configuration choice. It will
replace any audio signal already present
on the selected group or groups. To clarify,
the SDI signal connected to the input
will pass through to the output but audio
already present on the group or groups
selected to be embedded by the Model
5152 will be replaced.